The present invention relates to play and/or exercise hoops of the type known as HULA HOOPS.
Play hoops are widely known. They are used for rolling and gyrating about the hips and other parts of the body. Hoops are typically made from a length of plastic tubing by bending the length into a circle and joining the ends.
Such hoops do not have any internal damping, which restricts their efficiency. To gyrate a conventional hoop about the hips requires considerable work because the needed rotational speed is quite high.
Another drawback of previous hoops is that they are too light. The conventional hoops can be made of heavier-walled plastic tubing, but this is expensive and makes for difficult bending into the required circular form.
One previous hoop designed by the present applicant had contained water in an attempt to solve these problems, but this earlier liquid-filled hoop was not successful. The water leaked out and the hoop did not function properly.
An object of the present invention is to provide a play and/or exercise hoop which has internal damping. Another object is to make a hoop which has greater mass without the use of heavier and more expensive materials. Still another object is to provide a hoop with internal inertia shifting.
These objects are met by partially filling a hollow tubular hoop with water or some other liquid, preferably one at least as heavy as water. The trapped water increases the mass, provides internal damping of any motion (especially axial acceleration or deceleration), and leads to novel motions because of the shifting of the water inside.
Unlike the previous water-containing hoop, the circular hoop of the present invention allows the trapped water or liquid to freely circulate all the way around the hoop circumferentially; thus if the hoop is rolled slowly, the liquid remains in the lower part and the rolling motion of the hoop is smooth. The flow of the water around the circumference of the hoop must not be blocked if desirable toy dynamics are to be achieved.
The water filling of the present invention makes the typical HULA-HOOP hip gyration in which the hoop remains elevated, and similar gyrations, easier. This is because the water decreases the rotational speed needed in the hip motion. Centrifugal force causes the water to shift as the circular hoop is rotated or gyrated about the hips, permitting a slower, easier and less tiring rotation.
The water-tight hoop joint of the present invention includes a coupling tube, disposed inside the outer main hoop tube at the joint, having a large bore through which the liquid can freely flow. The coupling tube is preferably adapted for a seal, such as an O-ring, to be placed between the outer wall of the inner coupling and inner wall of the outer hoop tube.
The present invention also contemplates a method of making such a hoop and the construction of such a hoop, so that the hoop is both inexpensive and leak-proof.